Why would I want clothes to last until they look dated and unfashionable?
Also it would cost you less money to buy better quality clothes in the long run.
And yes, I've noticed that you do save money buying better made clothes that don't disintegrate in one season of wear.
Fashion can be timeless, even if its only a subset.
If you're a designer, you cant keep sending the same clothes down the catwalk year after year, if you design for a client, you cant really design the same stuff as last time.
Everybody does it, even the software industry, the clothing industry just does it at a higher tempo.
Ultimately, you don't have to play the game if you don't want to. The most stylish people I know don't really follow what's fashionable, and then there's me with jeans, t shirt, and a nearing on 20 year old jumper (that's vintage right?). If anything 'fashion' just seems to be a keeping up with the Joneses thing, rather than about looking good.
But jeans you can't wash >5 times? What kind of jeans can't hold up to that? Of all my clothes, jeans are my most durable by a long shot.